/*=====================================================================*
 *                   Copyright (C) 2011 Paul Mineiro                   *
 * All rights reserved.                                                *
 *                                                                     *
 * Redistribution and use in source and binary forms, with             *
 * or without modification, are permitted provided that the            *
 * following conditions are met:                                       *
 *                                                                     *
 *     * Redistributions of source code must retain the                *
 *     above copyright notice, this list of conditions and             *
 *     the following disclaimer.                                       *
 *                                                                     *
 *     * Redistributions in binary form must reproduce the             *
 *     above copyright notice, this list of conditions and             *
 *     the following disclaimer in the documentation and/or            *
 *     other materials provided with the distribution.                 *
 *                                                                     *
 *     * Neither the name of Paul Mineiro nor the names                *
 *     of other contributors may be used to endorse or promote         *
 *     products derived from this software without specific            *
 *     prior written permission.                                       *
 *                                                                     *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND              *
 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,         *
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES               *
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE             *
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER               *
 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,                 *
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES            *
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE           *
 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR                *
 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF          *
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 *                                                                     *
 * Contact: Paul Mineiro <paul@mineiro.com>                            *
 *=====================================================================*/

#ifndef __BLOCKOPT_HH__
#define __BLOCKOPT_HH__

#include <stdint.h>
#include <vector>

#include "fastonebigheader.hh"
#include "rating.hh"

namespace playerpiano
{
  template<typename PRating,
           typename Distribution>
  float
  blockopt (uint64_t                    t,
            float                       eta,
            float                       rho,
            std::vector<uint64_t>&      last_t,
            PRating&                    prating,
            unsigned int                n_items,
            float&                      logbeta,
            std::vector<float>&         pz,
            const std::vector<float>&   logpriorz,
            const std::vector<Rating>&  ratings,
            const Distribution&         priorlogbeta,
            bool                        test_only)
    {
      if (! test_only)
        {
          for (unsigned int i = 0; i < ratings.size (); ++i)
            {
              prating.apply_deferred_prior (ratings[i].worker,
                                            last_t[ratings[i].worker],
                                            t,
                                            eta,
                                            rho,
                                            n_items);

              last_t[ratings[i].worker] = t;
            }
        }

      float q = 
        em (prating, logbeta, pz, logpriorz, ratings, priorlogbeta, 100, 1e-3);

      if (! test_only)
        {
          float beta = fastexp (logbeta);

          for (unsigned int i = 0; i < ratings.size (); ++i)
            {
              prating.update (t, eta, rho, beta, pz, ratings[i]);
            }
        }

      return q;
    }
}

#endif // __BLOCKOPT_HH__
